I'm not trying to argue with you Lloyd. I wonder how much fuel.you'd have though if you ran at 1200hp for more than the 5 seconds on the dyno. What kind of RP do you see for those 5 seconds and would they be there for long ?

You obviously have the means to use many different components, a shop to do the work and the knowledge to do it too. I wasn't asking you to prove anything. I just thought you'd be interested in seeing if it helped or not and that in turn would have been able to help those that ask on the forums....

If you're not interested fine.... I was only trying to help answer Barry's questions, not stick out my chest with hp numbers

 

not that I am not interested, but put yourself in my place. I try to offer my advice free and get beat over the head with what I coulda and shoulda done. Get the fuel in the rail and you will not have an issue with fuel delivery

 

I could see extruding for better flow, but if your draining your rail with said "CP3 pump" I can't see making the rail hold more fuel is going to keep your rail pressures longer?

Here is my thought, We have tanks at work that we hydro test, we fill them completely with water (no air) then we pressurize to 40psi. (with a hydro pump, looks like a hydralic jack) And if we let one drop of water out of the tank it will drop to 0psi. Yes with one drop of water. So I guess my thought on this subject is you can have a rail the size of your truck bed, but it isn't going to do anything if your pump can't keep up with what your injectors are trying to put out.

 

This thinking makes the most sense to me.

In addition, if you're not losing RP then a modded rail isn't going to help. If the fuel supply to the injectors is there it's there.

 

Fuel is a liquid...and it is not compressible. The larger rail will not store "more energy" as compared to an air compressor tank...they are not comparable. The only “purpose of the rail is to provide enough area to hook fuel lines up to. A rail with smooth internals and the “right size” of internal bore is all that is needed to provide fuel without flow loss due to restriction/friction “k” factors.

The drop of water to cause pressure loss comment is the most spot on comment in this whole thread.

Supply is the key.

The largest restriction in the whole fuel system is the total open area of the injector tip hole anyway!

 

I just read a post by (Goober) & I think it might be relative to a Modded Rail.

if you understand pump theory u can understand why the horn works so well.
In a fire truck when u pump your attack lines you have to pump them at 10psi per 50feet more. So you have 100feet of 1 1/2 hose on the ground you have 20psi of friction loss so 100psi at the truck is 80psi at the nozzle. So you have to pump at 120psi to get 100psi at the nozzle but there is a problem if you get 500 feet of hose on the ground and you need 100psi at the nozzle you have to pump the truck at 200psi. Here is the problem, that much pressure causes turbulence in the hose, causing more friction loss. Now u take that same 500 feet of hose and you use 2 1/2 hose witch is 1.5psi of friction loss per 100 feet so instead of pumping 200 psi you only have to pump 107psi to get 100 psi at the nozzle and on top of the less pressure you have to pump you also get 3x GPM.

So by taking out a 1 1/2 restriction and making it a 3in port you cause less resistance and less turbulence witch = more air witch makes more power.

He is applying this to a intake horn but its all about hydraulics.
Do you think a modded rail could help maintaining pressure over a stock rail?

 

I guess my thought on this subject is you can have a rail the size of your truck bed, but it isn't going to do anything if your pump can't keep up with what your injectors are trying to put out.[/QUOTE]


This is what I've been saying for soooo long, we have tested modded rails of customers that they bought for thier truck and we have yet to find one make more HP.

John

 

Good post.

I do, but only if the stock rail isn't able to maintain adequate pressure. If the stock rail isn't being drained then how would the modded rail help?

 

Wow what a debate this thing has blown up into.
I see the logic behind the modified rail, and see the reasoning for those who say it is not needed. I really agreed with Lloyds post stating that if your stock cp3 cant keep the stock rail full why would it be able to keep a larger rail full. But if you can fill it the fuel will last longer, etc.
I do know of a couple of trucks running modified rails and one of which was RC's truck we talked to the TC guys awhile back and he was wondering how close we were to willis and if we knew RC he was a customer. Also Brett at Industrial Injection has also told us that they use the TC rails and have seen some gains in power from them. Not sure if the PDI truck, CT perf., and the FASS truck are running them but all are big supporters of II stuff and brett seemed adament in using them so one can only assume.

As for those who have proved that they arent needed you can look at rebs truck and Lloyds which are the two highest hp CR's in the country right now.

I think the only way to solve this problem is to get ahold of a truck with problems with draining the rail and a stock or diy cp3 and do some dyno testing.

 

this is the same theory as the flow of electrons, the bigger the wire the less resistance. the problem is air and fluid hydraulics to two different things. They can't be measure the same.

IMO, .. a modded rail is nothing more than a larger storage tank. It doesn't make hp by itself. It's there to provide extra fuel if called for. Whether it works to do anything... I don't know just like most.

Yes, if the pump keeps up with the demand you really wouldn't think it does a thing because the fuel it always there.

I think of it like a water tower. Open up the valve ( injector ) at the bottom of a smaller tower, only so much water will come out. Open up valve ( injector ) at the bottom of a larger tower... you have the same amount of water coming out but, it comes out a little longer because of the extra volume.

The bigger the valve ( injector ) at the bottom, the faster the water will drain. If you have a bigger tank, it won't empty as fast. With two pumps filling and maintaining pressure... I'd say you have all you fuel you'll need.

I know there are those that make plenty of hp with a stock rail. This was just my theory and lymans explaination

 

Lloyd can testify and so can we (two highest CR trucks in the country)... it is better to spend money elsewhere. If you have a couple hundred to blow... Go for it. I'd much rather spend the money on a nice external wastegate to flow more air. That is proven HP.

 

It doesn't make much sence to have a passage in the rail larger than than the line feeding it. You can't at the same pressure flow more than the smallest restriction in the circuit. The injector tip is the smallest.

 

I know when I put on the modded rail, I was able to maintain higher RP when initially going WOT. IMO this is really about the only point it seems to help. This is with a stg 3 pump and 150 injectors.

 

I believe that you guys are missing a major point,, size of injectors. I am quite sure that if I was to run a stock rail with the particular injectors that I am running right now I would see a power loss. I think that my truck is a very good show for the bigger rail. I dont have twins, I dont even have a particularly large turbo. I have sub standard electronics for big power (diablo). And I am running less nitrous than some,, and yet I am pulling over a thousand hp.

I could go to smaller injectors and probably get good numbers with a stock rail and lots of nitrous. But I wont find out, cause I know what direction I am going,, lol.

Kevin

 

It's not the rail size but the ability to fill the rail and keep the pressure at the desired level.... Having a larger volume of fuel in the rail does not good if the pressure of the rail drops.